Such a pillow, which can also be called a cervical pillow, provides the user with a more comfortable sleeping or resting position, by providing support for the neck and throat of the user, so that the user's head will not be angled unnaturally in relation to the user's body when in a resting position. The core of such a pillow, which may made of polyurethane foam, needs to be relatively solid and compression rigid, in order to retain its anatomical shape and fulfil its supportive function when subjected to the weight of the user's head and throat/neck parts. However, there is a risk of soft tissue, particularly the soft tissue of the neck/throat, being subjected to an excessively high pressure, or of the cervical vertebrae being subjected to excessively large shear forces, especially when the user lies on his/her stomach or back. Although the neck section of the pillow will have a greater spring length because of its height and can therefore be made more resilient or springy than the head section and therewith feel softer, this has not been found sufficient to compensate for the necessary hardness or firmness of the pillow core. These mutually contradictory requirements with regard to shape-rigidity and softness have not been resolved satisfactorily hitherto.
A person sleeping or resting on his/her side will normally also require a firmer or higher support against his/her head and neck and will therefore often use a hand, a lower arm or an upper arm to obtain a natural, firmer support or a higher support, so as to rest more comfortably. Known neck pillows normally have a constant height and constant lateral firmness, with the result that such pillows are too hard or solid against the user's neck when the user lies on his/her back. Furthermore, such pillows press much too hard against the user's throat when he/she lies on his/her stomach, and subjects the cervical vertebra to an ergonomically negative, backwardly bent and rotated outer position.
Seen against this background, an object of the present invention is to provide a neck pillow of the kind defined in the introduction which is more correct anatomically and more user-comfortable than known neck pillows, and which will adopt an anatomically neutral position both when the user lies on his/her back or on his/her side, and reduce the outer position when the user lies on his/her stomach.
Because there is formed in the resilient material of the core a cavity or aperture that extends transversely across the centre of the neck section and opens out through one side of said neck section, there is obtained in a surprisingly simple and material-saving fashion a pillow that includes a locally softer supporting part, primarily for supporting the user's head, neck and throat when the user lies on his/her back or stomach. There is thus achieved simultaneously the desired variation in firmness in a lateral direction or along the length of the neck section, so as to achieve the desired softer support against neck or throat when the user lies on his/her back or stomach, by virtue of the cavity being positioned centrally of the neck section.
When the cavity or aperture has the form of a channel that extends transversely across the neck and head section of the pillow, the variation in firmness, or hardness, extends along the length and up to the head section. The head section may normally need to be somewhat firmer than the neck section, and consequently that part of the channel which extends transversely to the head section will preferably have a smaller cross-sectional area than that part of the channel which extends transversely to the neck section. The smaller cross-section can be obtained by narrowing the channel in the head section. Alternatively, the smaller cross-section can be obtained beneficially by gradually decreasing the height of the channel with increasing distance from the channel orifice at the neck section; this is particularly advantageous when the head section slopes slightly from a higher to a lower side of the pillow, in that this sloping of the main section is compensated for by corresponding sloping of the "roof" of the channel. In one preferred embodiment, the channel has a generally arcuate or semi-elliptical cross-sectional shape.
These and other features of the invention will be apparent from dependent Claims and from the following detailed description made with reference to exemplifing embodiments thereof and also with reference to the accompanying drawings.